I was completing a sugar bowl on my lathe and started to wonder whether 5-minute epoxy would be usable to finish the interior. I didn’t try it out, but thought that someone here might have. My thinking was that the epoxy could be wiped on the interior of what is, essentially, a small bowl, with the lathe running slowly. The epoxy is thick enough that there wouldn’t, in theory, be much sag before it sets up. Have any of you tried this out?

You can try it. 5min epoxy sets up to fast to be used for a finish it won’t self level. One of the features you want in a finish is the ability to self level and fill in the small imperfections you level in a finish once you have applied it. I use epoxy finish on fishing rods and some woodworking project. I apply the finish with a brush at about 8 to 10 rpm and let it rotate at that speed for about 5 or 6 hours until it has cured enough it won’t sag. It is usually tack free in 24 hours.Some people will apply t about 100-150 rpm I think at that speed you get some finish slinging off and making a mess.

Alumilite sets up overnight not a 5min epoxy. It would probably work for your bowl but you would need to keep it rotating for a number of hours. You would need to apply a thin coat. the epoxy while self leveling want so run down hill. I have to keep the rod and spindle turning level or the epoxy runs downhill on the rod or turning. With a bowl centrifugal force might force the finish to the rim as it is setting up.

Skip the 5 minute as mentioned sets up too quick and several other issues.

On wood, depending on pore size, you will also need to seal your piece or very common to get bubbles trapped in the finish. A torch or just blowing on it can pop them but in 5 minute doesn’t give you a lot of time. The other issue is a lot of the 5 minute epoxies yellow in time. These epoxies are also very thick and don’t wipe well. For a nice finish they need to put on in a thick enough coat and allowed to self level not like super glue on a turning.

A 30 minute would be much better. I use 30 minute typically to seal lures and rotate them (Devcon typically or Bob Smiths) but I still don’t handle/touch the finish until the following day. I rotate (similar to the above rates) using a rotisserie motor to allow the stuff to sell level. To fast of an RPM and it does not let the epoxy flow but makes it stay in place and you get an uneven finish. If not applied to thick you can invert for a little while, flip back, and forth during that 30 minutes then leave to set up (method used on lures frequently but still can get uneven finish/pooling easily). Envirotex lite may be better for your application. Goes on thinner and takes usually overnight to set before handling.

The curve in the bowl will make it virtually impossible to prevent some runs developing before the epoxy sets up. The lathe rotation is only on one axes and unlike a spindle shape where the fluid would flow around that axes the bowl needs to rotate in a multi axis manner to keep the flow of fluid even across the whole surface.

My suggestion is to use one of the salad bowl finishes made by Behlen or General. Three or four coats creates a nice durable finish. You can apply two coats in one day, sanding or buffing lightly with 0000 steel wool between coats. I usually put on two coats then sand lightly and depending on the wood add two more coats. If you want a thicker finish keep adding more coats.